One goal of plant breeding is to combine, in a single hybrid or variety, various desirable traits. For field crops, these traits may include resistance to diseases and insects, resistance to heat and drought, reducing the time to crop maturity, greater yield, and better agronomic quality. Uniformity of plant characteristics such as germination and stand establishment, growth rate, maturity, plant height and fruit size facilitates mechanical harvesting. Traditional plant breeding through the development and use of inbred varieties facilitates the development of new and improved commercial crops.